People's perceptual skills can significantly affect their abilities to make optimal decisions, judgments, and actions in real-world dynamic environments. Perceptual learning refers to training and experiences to induce improvements in the ability to make sense of what people see, hear, feel, taste or smell based on ambiguous sensory information. In this study, investigators hypothesise that there exist neural signatures that robustly encode the conscious visual perception of rotations of a cursor and the magnitudes of these rotations in a novel, rotation-based perceptual learning task. Investigators also hypothesise that online, instantaneous EEG-based feedback on subjects' visual perceptions of rotations with an EEG-based Brain Computer Interface (BCI) can foster perceptual learning much more effectively than behaviour perceptual training, especially in very small rotation magnitudes that represent extremely difficult perceptual tasks.

Inclusion Criteria:

Able-bodied volunteers:

• good general health
• normal or corrected vision
• no history of neurological/psychiatric disease
• ability to read and understand English
• ability to understand information and ability to give a free and informed consent

Subjects with neuropsychiatric diseases

• Subjects with neuropsychiatric diseases such as bipolar disorder and schizophrenia.
• normal or corrected vision
• ability to read and understand English
• ability to understand information and ability to give a free and informed consent

Exclusion Criteria:

• short attentional spans or cognitive deficits that prevent to remain concentrated during the experimental sessions
• concomitant serious illnesses (e.g., metabolic disorders, cardiac arrest)
• factors hindering proper EEG acquisition (e.g., scalp wound, uncontrolled muscle activity)

All data will be made available by the online publication date. These data will be placed in public servers for any interested researcher to access it